Fuel-feeding means for charge-forming devices



March 13, 1928 1,662,128

- A. G. REDMOND FUEL FEEDING MEANS FOR CHARGE FORMING DEVICES Filed Jan. 3, 1923 a III! I Patented Mar. 13, 1928.

UNITED STATES v 1,662,128 PATENT OFFICE.

ALBERT G. REDMOND, OF INDIANAPOLIS, INDIANA, ASSIGNOR TO JACOB RICHARD FRANCIS, OF FLINT, MICHIGAN. v

FUEL-FEEDING MEANS FOR CHARGE-FORMING DEVICES.

Application filed {anuary 3, 1923. Serial No. 610,489.

This invention relates to certain new and useful improvements in means for supplymg fuel to charge forming devices used in connection with internal combustion engines and is an improvement on my application filed August 18, 1922, Serial Number 582,-

574, the object being to provide mechanical means for raising the piston of the pump for forcing the fluid from the main supply i tank to the charge forming device.

Another object of the invention is to provide a pump in which the stroke of the piston is determined by the quantity of fuel consumed by the internal combustion engine, mechanical means being provided for raising the piston, the weight of the piston displacing the fuel within the pump cylinder so as to force the desired quantity to the bowl of the charge forming device so as to maintain the fuel therein at a pre determined level.

A further object of the invention is to provide a construction of fuel feedin means which is exceedingly simple and cieap in construction and one which is readily installed on any of the well known types of internal combustion en ines now in use.

Other and further ObJGClS and advantages of the invention will be hereinafter set forth and the novel features thereof defined by the appended claim.

In the drawings,

Figure 1 is a side elevation of an internal combustion engine showing the application of my improved construction of fuel feeding means thereto; and

Figure 2 is a vertical section through the pump.

In the drawings 1 indicates an internal combustion engine, 2 the intake manifold thereofand 3 the charge forming device, the above description being given so that the operation of my improved construction of fuel feeding means can be readily undert-a'; stood.

Mounted on one side of the internal combastion engine is a pump cylinder 4 which is provided with a threaded lower end in which the nipple of a valve casing 5 is secured in which is mounted a ball check valve 6. Connected to the valve casing 5 is a fuel pipe 7 extending from the main fuel tank 8. The pump cylinder dis provided with a laterally extending nipple 9 having a threaded vertical bore in which is secured the reduced end of a valve casing 10 provided with a ball check, valve 11 and to which is connected an outlet pipe 12'having its other end connected to the fuel bowl of the charge forming device 3 in the ,usual manner.

' Connected to the upper end of the pump cylinder 4 is a pipe 13 having a plug 14 at its u per end provided with a square bore not s iown, in which is slidably mounted the squared end portion 15'of "a piston rod 16 carrying a piston 17 at its lower end working within the pump cylinder, the downward movement of which is limited by a stop 18 as clearly shown.

The upper end of the piston rod is provided with alateral extension 19 adapted to. be engaged by the lateral extension 20 of a lift rod 21 which is provided with a head 22 arranged over an eccentric 23 carried by a shaft 24 which is driven by the engine and is preferably so timed that the shaft makes one revolution every twenty revolutions of the engine, but, of course, this can be changed without departing from the spirit of my invention. The shaft is adapted to be driven by the engine in such a manner that when the lift rod 21 is raised,- the piston within the pump will be raised so as to force fuel from the main fuel tank 8 into the pump cylinder.

When the lift rod drops by gravity, the piston drops by gravity so as to force the fuel within the pump cylinder through the pipe 12 into the charge formin device. The lift rod is preferably mounte in bearings 24 and as the piston rod is so mounted that it is prevented from rotating, the piston will be raised and allowed to drop. by its own weight.

The weight of the piston is so adjusted that the pressure exerted on the fluid by displacement in the pump cylinder will be insufficient to overcome the pressure maintained on the check valve of the float cham- 100 ber of the carburetor so that the fuel in the pipe 12 will be held under pressure at all times. When the fuel is consumed in the fuel bowl of the charge forming device so as to allow the float to drop, the fuel in the 106 pipe line 12 instantaneously flows into the float chamber of the carburetor so as to maintain the predetermined level therein.

By constructing a fuel feeding means with a pump of this character, a displacement WP pump is formed in which the movement of the piston of the pump is actually determined by the quantity of fuel consumed by the charge forming device. The piston is held in its raised position by the pressure of the fluid within the pipe line 12 and pump cylinder and therefore the stroke of the piston is determined by the fuel consumed so that the fuel supply is automatically regulated by the consumption of fuel.

When the fuel in the pipe line 12 has been entirely consumed, the piston makes a full stroke in both directions and as the pipe line and pump cylinder become filled with fuel, back pressure is exerted on the same so as to maintain the piston in full or partially raised position whereby the stroke of the piston by the lift rod is reduced and as the fuel is consumed, is increased.

This provides means for supplying fuel constant y to the charge forming device by means of a particularly constructed pump which maintains fuel in the fuel line from the pum cylinder in the charge forming device un er pressure at all times so that the instant the fuel in the fuel bowl drops below a predetermined level, fuel is supplied thereto.

From the foregoing description it will be seen that I have provided a novel form of fuel feeding means for charge forming devices in which fuel is sucked from a main fuel supply below the level of the charge forming device into a pump cylinder from which it is forced by the falling weight of a piston into the charge forming device and as the end of the pipe carried by the pump cylinder is above the fuel level of the charge forming device, all danger of leakage is prevented and a construction of fuel feeding means is provided which is automatic or controlled by the moving part of an internal combustion engine in such a manner that a constant supply is provided for the charge forming device.

While in the drawing and specification I have shown and described a weighted piston for forcing fuel from the pump cylinder to the charge forming device, I am aware that a light piston could be employed over which is arranged a calibrated spring for forcing the piston downwardly with sufficient pressure to maintain the fuel in the line leading from the pump cylinder to the charge forming device under pressure at all times so that when the float in the fuel chamber of the charge forming device drops below a predetermined level, fuel will be instantaneously forced into the fuel bowl of the charge forming device and therefore I do not wish to limit myself to the use of a weighted piston of a predetermined weight as I have found by experimenting that a spring for forcing the piston downwardly after it has been raised will maintain the fuel under the desired pressure so that the instant the inlet of the fuel chamber of the charge forming device is opened, fuel will be delivered thereto.

\Vhat I claim is The combination with a motor vehicle having an internal combustion engine provided with a charge forming device and a fuel tank for supplying fuel to said charge forming device, of a vertically disposed displacement pump in communication with said tank and said char e forming device, said pump having a weighted piston provided with a non-rotatable )iston rod having a lateral extension, a lift rod having an extension arranged under the extension of said piston rod and means driven by the engine for raising said lift rod intermittently to allow said piston to drop by gravity for forcing and maintaining the fluid in the. pipe line leading to the charge forming device under pressure.

In testimony whereof I hereunto affix my signature.

ALBERT G. REDMOND. 

